Variable discharge pump and control therefor



June 5, 1951 c. F. ERIKSON 2,555,479

VARIABLE DISCHARGE PUMP AND common THEREFOR Filed July 11, 1947 4 Sheets-Sheet l INVEN TOR. CARL FER/KSON BY mam A T TO RNEY June 5, 1951 c. F. ERIKSON 7 VARIABLE DISCHARGE PUMP AND CONTROL THEREFOR Filed July 11, 1947 4 Sheets-Sheet 2 IN V EN TOR.

CARL F ER/KSON BY Wmih/m ATTORNEY June 5, 1951 c. F. ERIKSON 2,555,479

VARIABLE DISCHARGE PUMP AND CONTROL THEREFOR Filed July '11, 1947 4 Sheets-Sheet z IN V EN TOR. CARL EE/KSON BY Maw m ATTORNEY June 5, 1951 c. F. ERIKSON 2,555,479

VARIABLE DISCHARGE PUMP AND CONTROL THEREFOR Filed July 11, 1947 4 Sheets-Sheet 4 ATTORNEY GARLE ERIKSON win/mm Patented June 5, 1951 VARIABLE DIS CHARGE PUMP AND CONTROL THEREFOR Carl F. Erikson, White Plains, N. Y., assignor to Nathan Manufacturing Company, New York, N. Y., a corporation of New York Application July 11, 1947, Serial No. 760,203

11 Claims. (01. 103--38) This invention refers to variable discharge pumps and controls therefor, and has particular application to hydraulic pumps which discharge a liquid into a line to maintain certain pressure or flow conditions.

It is an object of the invention to provide within a suitable housing a plurality of pumping units operated in unison by a single member, and provide novel mechanism for adjusting the discharge from each of the pumping units simultaneously.

Other objects will become apparent in the following specification and in the accompanying drawings in which a preferred embodiment of the invention is disclosed.

In the drawings,

Fig. 1 is a longitudinal sectional view, partly in elevation, of the pump assembly with pistons in non-pumping positions, i. e., at Zero stroke;

Fig. 2 is a fragmentary cross-sectional view along the plane of line 2-2 in Fig. 1;

Fig. 3 is a cross-sectional view along the plane of line 33 in Fig. 1;

Fig. 4 is a cross-sectional view similar to Fig. 3, but the pump adjusted for maximum discharge;

Fig. 5 is a cross-sectional view along the plane of line 55 in Fig. 1;

Fig. 6 is a fragmentary cross-sectional view along the plane of line 66 in Fig. 1;

Fig. 7 is a diagrammatic view showing a driving plate, a regulating disc, and the pumping units at Zero stroke corresponding to Fig. 3, but taken along the plane of line 'l-1 in Fig. l. in the direction of the arrow shown;

Fig. 8 is a side view of Fig. '7;

Fig. '7 is a diagrammatic View similar to Fig. 7 but showing the pumping units, driving plate and regulating disc at maximum discharge;

Fig. 10 is a side view of Fig. 9; and

Fig. 11 is a development of the pumping units along a straight line showing diagrammatically the relative positions of the various units.

Like characters of reference denote similar parts throughout the several views and the following specification.

20 is a pump housing having an inlet 2| and an outlet 22 at on end. Its other end is closed by a cover 23. 24 is a block having a plurality of cylinders 25 provided with transverse openings 26 and 2'! in alignment with each other. Open- 'ings 26 through a central cavity 28 in block 24 communicate with inlet 2|, and openings 21 through an annular well 29 in housing 25 communicate with outlet 22.

A drive shaft 35 centrally disposed within the housing 20 is supported by cover 23 and extends exteriorly thereof to connect with suitable driving means (not shown). Drive shaft 30 has a central eccentric portion 3| having a large diameter 32 and a relatively small diameter 33. Shaft 35 terminates within the housing in an end 34 coaxially supported by a ball bearing within the center of block 24 as shown in Fig. 1. End 34 is fastened to the eccentric portion 31 of drive shaft 30 by suitable means such as a bolt 36. Fitted to shaft 30 and adapted to turn therewith is a plate 31 carrying a counterweight 38, the plate being supported within the cover 23 by a ball bearing 39.

A driving plate 40 is supported axially upon the eccentric portion 3| of drive shaft 30 by a ball bearing 4| upon its large diameter 32 and by a ball bearing 42 upon its small diameter 33.

43 is a piston in each of the cylinders 25. While th drawings show nine pistons and cylinders, any desired number more than one, of course, may be used. Each piston 43 has at its innermost end a longitudinal bore 44 open to the cylinder and a transverse duct 45 adapted to communicate alternately with openings 25 and 2'! and through bore 44 with the cylinder as will be explained later. The outer end of each piston 43 is slotted at 46.

41 is a connecting rod which has one end flattened at 48 and pivoted to the slotted end 46 of the piston 43 by means of a pivot 49 forming a clevis joint between the connecting rod and the piston. The other end of the connecting rod 41 terminates in a ball 50.

That part of the driving plate 46 which faces the pistons 43 has a number of round sockets 51 substantially at right angles to the axis of the drive shaft, one socket for each piston. In each of the sockets are two bearing halves 52 cupped out at opposite faces to receive a ball terminal 55. 53 is a circular band around the periphery of plate 45, closing sockets 5|. 54 is a slot in each of the sockets to clear the connecting rod immediately adjacent the ball terminal. A spring 55 in the socket forces the bearing halves together and confines th ball terminal between them.

The piston, connecting rod, and method of attaching the rod to the driving plate are essentially the same as disclosed and claimed in another application filed simultaneously with the instant one.

56 is a regulating disc mounted upon a ball bearing around drive shaft (ill as shown in Fig. 1. Disc 55 is connected to driving plate t!) by means of two links 58, each being pivoted to the disc 56 by a pin 59 and to the plate 40 by a pin Gil, the distance between the pivots 59) and til being the same as the eccentricity of eccentric portion 31 of the drive shaft 3% with respect to its axis. 6! is a handle bar having a lateral pin 52 fastened to the disc 56 by a set screw 6%. Handle bar 6| projects exteriorly of the housing 2!] through a slot 6 for convenient manipulation.

Referring to Fig. 1, it will be seen that rotation of drive shaft 36 causes an oscillation of the driving plate All in such a way that each ball terminal moves in a circle of which the piston axis larly liquid is drawn into the cylinder through passage and inlet 2! on its outward or suction stroke.

The entire adjustment of the pump is effected by a simple manipulation of the handle bar BI. Because the zero stroke is at a central position, and adjustment can be made by moving the hanidle bar in either direction, the direction of flow in the pump can be reversed.

If it is desired to disassemble the pump, it is only necessary to loosen the set screw 63 to disconnect the handle bar 6| from the regulating disc '56 while the driving plate 40 is in a position about opposite 'to the one shown in Fig. '1, when is located in the center and the radius is equal,

to the eccentricity between the axis of the drive shaft and its eccentric portion 3|. 'All ball terminals move in a plane perpendicular to the axis of the drive shaft. The connecting rod 41 maintains the same conical angle with the pivot 49 on the piston, and no reciprocation of the piston takes place, but rotation only. This is the zero stroke position, as also clearly brought out in the diagrams of Figs. '7 and 8 in which the ball terminals and the piston pivots are shown to travel in parallel planes and the connecting rods at the same angle with respect to the piston axis. By pushing the handle bar 61 of the regulating disc 56 to the right as shown in Fig. 4, and also in diagrams in Figs. 9 and 10, by an angle A, the regulating disc 56 is slightly rotated to the extent of angle A around the axis of drive shaft 30 which by means of links 58 move driving plate 40 about the axis of the eccentric portion 3| of shaft 313 to the extent of the same angle A by virtue of the length of the links which corresponds to the eccentricity between .shaft 30 and its portion .3 L relation to each other as shown clearly in Fig. 9. The ball terminals move in the same plane as before, perpendicular to the drive shaft axis. The relation between each ball terminal 50 and its piston 43, however, is changed because the angle which the connecting rod describes around the pivot 49 is not the same with respect to the piston axis, but is less to one side and more to the other according to the distance the center of the circular travel of the ball terminal 50 has 7 been shifted by the regulating disc 5t away from a plane through the axis of the piston. The connecting rod being of fixed length, reciprocation of the piston now takes place as indicated in Fig. 10 which shows the pivot 49 of the various pistons in different planes while, as stated before, all ball terminals 50 travel in the same plane.

In Fig. 11 a development is shown indicating the progressive positions of the pistons during one complete cycle of the driving plate 40. As a ball terminal 50 is farthest away from the axis of its piston 33, the piston is in its highest positions. Its cylinder 25 is filled with liquid and openings 26 and 2'! are closed by the piston. Oscillation of the driving plate 30 then rotates ball terminal 58 in a circle the radius of which is equal, as stated before, to the eccentricity of shaft .36 with respect to its eccentric portion 3|. During this travel of the ball terminal 50,, the

The links maintain their parallel the .entire inner mechanism can be withdrawn with removal of the cover 23 and shaft 30.

While'I have shown only one inlet and one outlet to the pump, it is obvious that a number of inlets and outlets can be provided for and if so desired, one .for each individual pumping unit.

While the drawings show reciprocatory and rotary pistons controlling the cylinder inlets and outlets, I may use the reciprocating motion of the pistons only in combination with inlet and outlet check valves or other similar means well known in the art, in which case the pistons, .however, will be operated in exactly the same man- By admitting fluid under pressure, the pump may be used as a motor, an expedient well known in the art. 7

Many other modifications in the form, proportion, combination of parts and minor details of construction may be resorted to without departing from the principles or sacrificing any of the advantages of the invention as defined in the appended claims.

What I claim as new, is:

1. In a pump, a rotary -.drive shaft, a plurality of cylinders annularly disposed around the shaft, a reciprocatory piston in each cylinder, the-drive shaft having an eccentric portion, a driving plate movably mounted upon the eccentric portion, a connecting rod for each of the pistons having one end pivoted to the piston and its other end to the driving plate, whereby rotation of the drive shaft imparts an oscillating motion to the driving plate and each piston is reciprocated by the angular variation of its connecting rod with respect to the piston axis, and means, common to all connecting rods, to change the extent of the angular variation to adjust the stroke of the piston.

2. In a pump as defined in claim 1, the means to adjust the stroke of the piston including a regulating disc mounted upon the drive shaft and operably connected to the driving plate, means to vary the position of the disc upon the shaft whereby the position of the driving plate on the shaft will be changed and thereby the angular relation of each connecting rod with respect to its piston.

3. In a pump as defined in claim 1, the means to adjust the stroke .of the piston including a regulating .disc mounted on the drive shaft, a pair of pivoted links between the disc and the driving plate of a length equal to the eccentricity of the eccentric portion of th drive shaft, and means to vary the position of the disc on the shaft whereby the links change the position of the driving plate on the eccentric portion of the shaft and thereby the angular relation of each connecting rod with respect to its piston.

4. In a pump, a rotary drive shaft, a plurality of cylinders annularly disposed around the shaft, each cylinder having an inlet and an outlet, a rotary and reciprocatory piston in each cylinder having means for alternately placing the inlet and outlet in communication with the cylinder as the piston rotates, the drive shaft having an eccentric portion, a driving plate movably mounted upon the eccentric portion, a connecting rod for each of the pistons having one end pivoted to the piston and its other end to the driving plate, whereby rotation Of'the drive shaft imparts an oscillating motion to the driving plate and each piston is rotated and reciprocated by the angular variation of its connecting rod with respect to the piston axis, and means, common to all connecting rods, to change the extent of the angular variation to adjust the stroke of the piston.

5. In a pump as defined in claim 4, the means to adjust the stroke of the piston including a regulating disc mounted upon the drive shaft and operably connected to the driving plate, means to vary the position of the disc upon the shaft whereby the position of the driving plate on the shaft will be changed and thereby the angular relation of each connecting rod with respect to its piston.

6. In a pump as defined in claim 4, the means to adjust the stroke of the piston including a regulating disc mounted on the drive shaft, a pair of pivoted links between the disc and the driving plate of a length equal to the eccentricity of the eccentric portion of the drive shaft, and means to vary the position of the disc on the shaft whereby the links change the position of the driving plate on the eccentric portion of the shaft and thereby the angular relation of each connecting rod with respect to its piston.

7. A pump comprising a housing, a rotary drive shaft supported within the housing, a plurality of cylinders annularly disposed around the shaft, each cylinder having an inlet in communication with a common inlet in the housing and each cylinder having an outlet in communication with a common outlet in the housing, a rotary and reciprocatory piston in each cylinder having means for alternately placing the inlet and outlet in communication with the cylinder as the piston rotates, the drive shaft having an eccentric portion, a driving plate movably mounted upon the eccentric portion, a connecting rod for each of the pistons having one end pivoted to the piston and its other end to the driving plate, whereby rotation of the drive shaft imparts an oscillating motion to the driving plate and each piston is rotated and reciprocated by the angular variation of its connecting rod with respect to the piston axis, and means, common to all connecting rods, to change the extent of the angular variation to adjust the stroke of the piston.

8. A pump comprising a housing, a rotary drive shaft, a block containing a plurality of cylinders annularly disposed around the shaft, one end of the shaft being supported within the center of the block, each cylinder having an inlet and an outlet, a rotary and reciprocatory piston in each cylinder having means for alternately placing the inlet and outlet in communication with the cylinder as the piston rotates, the drive shaft having an eccentric portion, a driving plate movably mounted upon the eccentric portion, a con 6 I necting rod for each of the pistons having one end pivoted to the piston and its other end to the driving plate, whereby rotation of the drive shaft imparts an oscillating motion to the driving plate and each piston is rotated and reciprocated by the angular variation of its connecting rod with respect to the piston aXis, and means, common to all connecting rods, to change the extent of the angular variation to adjust the stroke of the piston.

9. A pump comprising a housing, a rotary drive shaft, a block containing a plurality of cylinders annularly disposed around the shaft, one end of the shaft being supported within the center of the block, each cylinder having an inlet in communication with a common inlet in the housing and each cylinder having an outlet in communication with a common outlet in the housing, a rotary and reciprocatory piston in each cylinder having means for alternately placing the inlet and outlet in communication with the cylinder as the piston rotates, the drive shaft having an eccentric portion, a driving plate movably mounted upon the eccentric portion, a connecting rod for each of the pistons having one end pivoted to the piston and its other end to the driving plate, whereby rotation of the drive shaft imparts an oscillating motion to the driving plate and each piston is rotated and reciprocated by the angular variation of its connecting rod with respect to the piston axis, and means, common to all connecting rods, to change the extent of the angular variation to adjust the stroke of the piston.

10. A pump comprising a housing, a cover at one end, a block containing a plurality of cylinders at its other end, a rotary drive shaft supported by the cover and the block, the cylinders being annularly disposed around the shaft, a reciprocatory piston in each cylinder, the drive shaft having an eccentric portion, a driving plate movably mounted upon the eccentric portion, a connecting rod for each of the pistons having one end pivoted to the piston and its other end to the driving plate, whereby rotation of the drive shaft imparts an oscillating motion to the driving plate and each piston is rotated and reciprocated by the angular variation of its connecting rod with respect to the piston axis, a regulating disc mounted on the drive shaft and operably connected to the driving plate adapted to be moved to change the angular relation of each connecting rod with respect to its piston, the cover, drive shaft, regulating disc, connecting rods and pistons adapted to be withdrawn from the housing as a unit.

11. A pump comprising a housing, a cover at one end, a block containing a plurality of cylinders at its other end, a rotary drive shaft supported by the cover and the block, the cylinders being annularly disposed around the shaft and each cylinder having an inlet in communication with a common inlet in the housing and an outlet in communication with a common outlet in the housing, a rotary and reciprocatory piston in each cylinder having means for alternately plac ing the inlet and the outlet in communication with the cylinder as the piston rotates, the drive shaft having an eccentric portion, a driving plate movablymounted upon the eccentric portion, a connecting rod for each of the pistons having one end pivoted to the piston and its other end to the driving plate, whereby rotation of the drive shaft imparts an oscillating motion to the driving plate and each piston is rotated and recipro- 7 3 i cated by the angular variation of its connecting REFERENCES CITED rod with respect to the piston axis regulating The following references are of record in the disc mounted on the drive shaft and operably file of this patent:

connected to the driving 'plate adapted to be moved to change the angular relation of each 5 UNITED STATES PATENTS connecting rod with respect to its piston, the Number Name Date cover, drive shaft, regulating disc, connecting 1,631,356 Banning, Jr. June 7, 1927 rods and pistons adapted to be withdrawn from 2,176,360 Price Oct. 1'7, 1939 the housing asaunit. 2,232,976 Schmied Feb. 25, 1941 10 2,369,345 Folke Feb. 13, 1945 CARL ERIKSON- 2,430,394 Folke et a1 Nov. 4, 1947 2,467,916 Shepard Apr. 19, 1949 

